That mysterious characteristic ""It"" - ""the easily perceived but hard-to-define quality possessed by abnormally interesting people"" - is the subject of Joseph R. Roach's engrossing new book. As he did in the prizewinning ""Cities of the Dead"", Roach crisscrosses centuries and continents with a deep playfulness that entertains while it enlightens. Roach traces the origins of ""It"" back to the period following the Restoration, persuasively linking the sex appeal of today's celebrity figures with those who lived centuries before. The book includes guest appearances by King Charles II, Samuel Pepys, Flo Ziegfeld, Johnny Depp, Elinor Glyn, Clara Bow, the Second Duke of Buckingham, John Dryden, Michael Jackson, and Lady Diana, among others.